just putting this here for posterity, a horse breeding chart
sample size: 10 million
columns from left to right:
average speed of parents, percentage chance that children is better, number of horses bred before a better child is found on average
11.00: 23.90%: 0004
11.50: 15.13%: 0007
12.00: 08.79%: 0011
12.25: 06.41%: 0016
12.50: 04.52%: 0022
12.75: 03.05%: 0033
13.00: 01.93%: 0052
13.20: 01.26%: 0080
13.40: 00.76%: 0131
13.60: 00.42%: 0238
13.80: 00.20%: 0499
14.00: 00.07%: 1341
advanced guide to using this chart:
suppose you have a parent which is 13 and a parent which is 12.8, and you want to breed another 13 or better. the average is 12.9, so you're off by 0.1, and since the third random horse is weighed by 1/3rd, you need a 12.9+0.1*3 = 13.2 m/s horse to be generated for the child to be 13.0 m/s , which will take you 80 breedings on average
in general, if the parents have speeds A and B, and you want to breed a child C, A <= B and (A+B)/2 <= C, look up the value in this table for 3C-A-B
so if the parents have speeds 12.7 and 12.3, and you want to breed 13, look up the value for 3*13-12.7-12.3 = 14, which has 0.07% chance
anyway this is enough to convince me that i've spent enough effort
